Surface Modification of Wood by Alkoxysilane Sol–Gel Deposition to Create Anti-mold and Anti-fungal Characteristics

Abstract

Hybrid inorganic/organic thin films deposited on wood substrates have been shown to lower the rate of moisture sorption of the wood. Deposition of such thin films can be accomplished by sol–gel deposition or by plasma-enhanced chemical vapor deposition. This paper describes in situ sol–gel deposition of hy­ brid inorganic/organic thin films on wood substrates using methyltrimethoxysilane (MTMOS) as precursor and trifluoroacetic acid as catalyst. MTMOS has desirable performance characteristics such as substrate penetration and water repellence. The surface chemistry of wood specimens coated with these thin films was characterized by Fourier trans­ form infrared (FTIR) spectroscopy and energy dispersive X-ray analysis (EDXA). Surface morphology was characterized by scanning electron microscopy (SEM). The effect of sol–gel-deposited thin films on mold growth and fungal colonization on wood surfaces was investigated. These thin films were shown to inhibit growth of mixed mold spores and decay fungi, Trametes versicolor and Gloeophyllum trabeum, on wood surfaces. Moisture resistance properties of the sol–gel thin film deposit may be the single most important contributor to the anti-mold and anti-fungal properties of the sol–gel-treated wood surfaces.